Generally, this disclosure relates to respirators that are worn on a user's head to provide breathable air for the user.
Respirators are well known and have many uses. For example, respirators may be used to allow the user to breathe safely in a contaminated atmosphere, such as a smoke filled atmosphere, a fire or a dust laden atmosphere, or in a mine or at high altitudes where sufficient breathable air is otherwise unavailable, or in a toxic atmosphere, or in a laboratory. Respirators may also be worn where it is desired to protect the user from contaminating the surrounding atmosphere, such as when working in a clean room used to manufacture silicone chips.
Some respirators have a helmet that is intended to provide some protection against impacts when working in a dangerous environment or when the user is at risk of being struck by falling or thrown debris such as in a mine, an industrial setting or on a construction site. Another type of respirator employs a hood when head protection from impact is not believed to be required such as, for example, when working in a laboratory or a clean room.
A respirator hood is usually made of a soft, flexible material suitable for the environment in which the hood is to be worn, and an apron or skirt may be provided at a lower end of the hood to extend over the shoulder region of the user. Hoods of this type are commonly used with a bodysuit to isolate the user from the environment in which the user is working. The apron or skirt often serves as an interface with the bodysuit to shield the user from ambient atmospheric conditions. Another form of hood is sometimes referred to as a head cover, and does not cover a user's entire head, but only extends above the ears of the user, and extends down about the chin of the user in front of the user's ears. The hood has a transparent region at the front, commonly referred to as a visor, through which the user can see. The visor may be an integral part of the hood or detachable so that it can be removed and replaced if damaged.
A respirator helmet is usually made from a hard, inflexible material suitable for the environment in which the helmet is to be worn. For example, such materials may include metallic materials such as steel or hard polymers. A respirator helmet typically will extend at least over the top of the user's head, and may have a brim around all sides thereof, or a bill extending forwardly therefrom, thereby providing additional protection over the user's facial area. In addition, such a helmet may also include protective sides extending downwardly from along the rear and sides of the user's head. Such sides may be formed from an inflexible material or may be formed from a flexible material. A respirator helmet has a visor disposed thereon that permits the user to see outside of the respirator. The visor may be transparent. However, in some instance, such as for welding, the visor may be tinted or it may include a filter, such as an auto darkening fitter (ADF). The visor may be an integral part of the respirator helmet or detachable so that is can be removed and replaced if damaged.
A respirator helmet is intended to provide a zone of breathable air space for a user. As such, the helmet is also typically sealed about the user's head and/or neck area. At least one air supply provides breathable air to the interior of the respirator helmet. The air supply pipe may be connected to a remote air source separate from the user, but for many applications, the air supply pipe is connected to a portable air source carried by the user, commonly on the user's back or carried on a belt. In one form, a portable air supply comprises a turbo unit, including a fan driven by a motor powered by a battery and a filter. The portable air supply is intended to provide a breathable air supply to the user for a predetermined period of time.